Shows references to static methods and fields
via a class instance rather than a class itself.
Example:
String s = String.valueOf(0); // correct: static method qualified with class name
String s1 = s.valueOf(0); // wrong: static method qualified with class instance
While allowed by Java Language Specification,
referring to static members via instance variables makes the code confusing
as the reader may think that the result of the method depends on the instance.
Quick fix: replaces the instance variable with the class name.